(CNSNews.com) – Sen. John McCain (R-Aiz.) said that it was “disgraceful” and “beyond belief” that the Obama administration would characterize the attack on the U.S. diplomatic outpost in Benghazi, Libya, was anything but a terrorist attack.

Speaking Thursday on the "CBS This Morning" program, McCain said that it was “unbelievable” that top foreign policy officials would claim the attack was a spontaneous demonstration.

“It was just unbelievable that [U.N.] Ambassador [Susan] Rice and Secretary [Hillary] Clinton and the White House spokesman and others would say that there is no evidence that this was a spontaneous attack,” McCain said.

“It was obvious, it was obvious, that this was a planned attack, that they carried heavy weapons, mortars, RPGs [rocket-propelled grenades]. Clearly, it was not a demonstration nor was it the result of a hateful video.”

Rice, on the Sept. 16 edition of NBC's "Meet the Press" said of the attack, which led to the deaths of U.S. Ambassador Chris Stevens and three other foreign service personnel:“This is a response to a hateful and offensive video that was widely disseminated throughout the Arab and Muslim world.”

McCain mocked the idea that such weapons would just show up at a reactionary, spontaneous demonstration: “[And] you say, ‘C’mon honey bring your mortars, we’re going to a spontaneous demonstration.’”

McCain called the Obama administration’s explanation -- which President Obama himself repeated in a speech to the United Nations Wednesday -- “disgraceful,” saying that anyone with a “fundamental” understanding of warfare could see that heavy weaponry would not be part of a spontaneous demonstration.

“It’s disgraceful that we would say an attack such as this, on its face, was the result of a demonstration,” McCain said.

McCain dismissed “CBS This Morning” co-host Norah O’Donnell, who challenged him “How do you know [it was an attack]?”

He responded: “Anybody who understands warfare, anybody who has the fundamental understanding of warfare knows that that’s not a spontaneous demonstration.”

McCain also called it “incredible naiveté” for the administration to blame the attack on a video clip that some Muslim radicals found offensive.

“Also, [it’s] incredible naivete to blame it on a video. It’s not the video, it’s the Islamists using the video,” he said. “To say this was a spontaneous demonstration is really beyond belief and shows a fundamental misunderstanding, not only of warfare but of what’s going on in that part of the world.”

McCain, the ranking Republican on the Senate Armed Services Committee, maintained there is "no possibility" that the attack was spontaneous.